1. Field of the Invention
This invention relates to a structure for retaining a front holder in a housing. The structure allows the front holder for preventing a terminal coming off to be retained in the housing while the front holder is inserted into the housing from an engagement surface side of the housing.
2. Background
FIG. 6 is a perspective view showing a conventional doubly retained connector which includes a housing and a front holder; FIG. 7 is a sectional view showing a condition in which the front holder is inclined in the housing; and FIG. 8 is a sectional view showing a relation between a flexion preventing plate portion and a refuge space in the condition in which the front holder is inclined in the housing.
A doubly retained connector 1 shown in FIG. 6 has been disclosed in Unexamined Japanese Patent Publication No. Hei. 8-203592. The connector 1 includes a housing 2 having a plurality of terminal receiving chambers 4 which are respectively receivable terminals therein, and a front holder 3 which is retained in the housing 2 from an engagement surface 2a side of the housing 2.
As shown in FIG. 8, flexible retaining lances 5 extend from an inner wall of the terminal receiving chambers 4, respectively. The retaining lances 5 have retaining stepped portions 6. The retaining stepped portions 6 respectively retain the terminals 7 received in the terminal receiving chambers 4, so as to prevent terminals 7 coming off from the terminal receiving chambers 4.
The front holder 3 includes a frame-forming main-body portion 8 and a plurality of flexion preventing plates 9 formed integrally with the frame-forming main-body portion 8 so as to project from the frame-forming main-body portion 8. The front holder 3 is inserted into the housing 2 from the engagement surface 2a of the housing 2 engageable with a mating connector. Furthermore, the front holder 3 is retained by the housing 2 at two positions, a regularly retained position and a temporarily retained position, with respect to the housing 2.
When the front holder 3 is in the regularly retained position, the flexion preventing plates 9 are respectively inserted into refuge spaces 10 under the retaining lances 5 in the terminal receiving chambers 4. Accordingly, inadvertent flexion of the retaining lances 5 can be prevented, and also the terminals 7 are doubly retained within the terminal receiving chambers 4.
On the other hand, when the front holder 3 is in the temporarily retained position, the flexion preventing plates 9 are evacuated from the refuge spaces 10 under the retaining lances 5 in the terminal receiving chambers 4. Under this condition, if a terminal 7 is inserted into a terminal receiving chamber 4, the corresponding retaining lance 5 flexes. When the terminal 7 is further inserted to be accommodated at a predetermined position within the terminal receiving chamber 4, the retaining lance 5 returns to the original shape by its own resiliency to thereby cause the retaining stepped portion 6 of the retaining lance 5 to be retained by the terminal 7.
On the other hand, in order to pull a terminal 7 out of a terminal receiving chamber 4, the retaining lance 5 can be forcibly flexed by a terminal releasing jig after moving the front holder 3 from the regularly retained position to the temporarily retained position. Accordingly, the terminal 7 can be pulled out of the terminal receiving chamber 4.
However, when the front holder 3 is in the temporarily retained position with respect to the housing 2, the front holder 3 may be inclined with respect to the housing 2 due to play in a direction of width as shown in FIG. 7. When the front holder 3 is inclined, one side of the width direction of the front holder 3 may be inserted unnecessarily into the housing 2. Accordingly, end portions of the flexion preventing plates 9 are undesirably inserted into the refuge spaces 10 of the retaining lances 5 as shown in FIG. 8. Since the retaining lances 5 are not allowed to flex under this condition, the problem that a terminal 7 cannot be inserted into a terminal receiving chamber 4 arises.
Furthermore, even if attempts are made to forcibly flex a retaining lance 5 by inserting the terminal releasing jig, the flexion preventing plates 9 regulate flexion of the retaining lance 5. From this arises the problem that the terminal 7 cannot be pulled out even if the front holder 3 is set in the temporarily retained position.